Warren Buffet could set up a secrete underground mining farm having more hashing power than the current network, secretly re-mining the whole blockchain up from the genesis block until his chain has more accumulated proof-of-work. He would simply mine empty blocks as he wants to destroy its value (remember his objective ). He would now publish his chain. My question: would now every node in the system switch to Buffets' chain thereby wiping out all history

We really plan to get rid of checkpoints, or at least significantly reduce their power. They don't actually add any security (if they would actually affect the chain, the system is already broken). – Pieter Wuille Sep 14 '14 at 20:47

How do in my scenario checkpoints not add to security? They actually would, right?

Yes that would be theoretical possible. But the underground hash farm must be very big for that and so you can say this case is only theoretical. Imagine you have really only 51% of the total hash power and you have to calculate every block from the beginning. This will take a lot. But if this is still a thought experiment let's assume what will happens then. Warren has done his majority attack so there is a longer chain with only empty blocks (I assume that all mining rewards are going into his wallets). This would put the price of this particular blockchain really fast down. But the historic blockchain is still stored on the nodes and all user of this blockchain will notice this attack. This can lead to a hard fork which resets the majority attack again.So in this scenario Warren had put a very big part of his money into an attack but probably have done a not so big damage (depending on if you use this blockchain as currency or speculation).

If there would be anyone or groups of attackers that could sabotage more than 50% of the blockchain networks then there's big possibilities that the entire blockchain will be compromised. But as of now, only the coin exchanges are vulnerable from hacks and attacks because attackers could get altcoins inside the coin exchanges but they couldn't get anything on attacking the entire blockchain networks.

Warren Buffet could set up a secrete underground mining farm having more hashing power than the current network, secretly re-mining the whole blockchain up from the genesis block until his chain has more accumulated proof-of-work.

First of all, this would take much more hashpower than what would equate to 51% of the network if released into the wild. Remember, Warren Buffet would need to catch up with more than 10 years of hashing while staying ahead of future hardware developments.

Second, I guess Warren Buffet's nodes would simply get blacklisted by the other nodes on the network, with Core releasing an emergency patch blocking Buffet's blockchain on a more fundamental level.

Such an attack would have an interesting side-effect though. Since such an alternative blockchain would have been mined with high-powered ASICs from the very start, the accumulated work of Warren's blockchain would exceed the amount of accumulated work of the canonical blockchain while still remaining on a different block reward cycle. In other words, if Warren Buffet manages to overtake the canonical blockchain within, say, 2 years, that would still be before the first halving on Warren's blockchain, since while the amount of work put into it would be larger, the amount of blocks being mined can't be accelerated without increasing the hashrate in a steady manner -- which would counteract the purpose of the attack, since in this case you would want to throw in all that you got from the very beginning.

But the true historic blockchain is only held in memory as a secondary chain. As soon as I switch of the node it would be lost. Probably my memory would overflow, anyway.

For Bitcoin Core (the most commonly used node software) that is completely false. AFAIK, all other full node implementations also follow what Bitcoin Core does, so that is false for them too. All valid blocks that are received are stored to disk, regardless of whether it is in the main chain. Nothing is removed from the on disk blockchain data either.

Of course there could be a full node software that only stores the main chain on disk and deletes blocks if they get orphaned. But that would be a fairly poor implementation which probably has a lot of problems.

Warren Buffet would end up creating an altcoin, and just like segwit2x, it would end up dead. If big exchanges support Warren Buffet's chain, (which means all these nodes would be supporting it) it would be a problem, they would attempt to reorg it and then list the new chain as "BTC" on all the tickers (just like segwit2x intended) but then again, the people running these exchanges would probably end up dead since Bitcoin $billionaires aren't going to sit on their ass and watch how some old fuck kills the legacy chain. Bitcoin is not a game and there's people with enough resources to get things done if things get really ugly at some point. Don't want to play around with that. Buffet or whoever attempts to do that would need to consider if it's worth the risk, when he could be making a ton of money by being a good actor in Bitcoin.

The only scenario that I see possible where the legacy chain gets reorged is if there is an exploit on SHA256 and therefore we are forced to change the algorithm to survive, at that point the consensus would be 100%, the problem would be to what algorithm should it be changed to, and if that is not agreed upon fast, Bitcoin would be vulnerable until then.

Unfortunately I am going have to use a bit of self censorship here but all system can be made to fail but the powers that be (PTB)have Microsoft on their side and making an educated conservative guess I would say they already know most of our private keysand even without access to Microsoft's dark hidden secrets I could steel public keys from most wallets without breaking into a sweat if I wasto install a little program or service on your windows based machine.

Audit your windows SSL store in the middle of the night when no apps are running for a few days and then tell me that we are notbeing watched and yes I am sure this "Bug" will get fixed in Microsoft security update 999,721 when enough people notice it.

Second, I guess Warren Buffet's nodes would simply get blacklisted by the other nodes on the network, with Core releasing an emergency patch blocking Buffet's blockchain on a more fundamental level.

You mean like someone is "Baby sitting" the block-chain ?

Sure I think a little bit goes on, don't mind it too much and I think some miners are able to un-stick transactions that are lost in the post but that does not put anyone in a position to steel the money themselves but of course that like to keep things like this quite.

I once lost on paper (Bad SQL Query) about $5m that was used in detailed top level management reports and spotted the mistake myself, fessed up quite openly and not a word was said because those at the top should have noticed it so enough said but if thathad been picked up by "Investors" then it would have had some real impact, my head would had rolled with a few more.

Mining is CPU-wars and Intel, AMD like it nearly as much as big oil likes miners wasting electricity. Is this what mankind has come too.

Second, I guess Warren Buffet's nodes would simply get blacklisted by the other nodes on the network, with Core releasing an emergency patch blocking Buffet's blockchain on a more fundamental level.

You mean like someone is "Baby sitting" the block-chain ?

No need for "babysitting" the Bitcoin blockchain. It's a question of individual nodes making sure that they are using the canonical Bitcoin blockchain, lest they receive buffetcoins instead of bitcoins.

Cellard is pretty much on point with Warren Buffet merely ending up creating an alt coin.

(Side note: Gotta love the idea of a hypothetical Warren Buffet / John McAfee rivalry. Those businessmen are as different as can be. Old economy vs new economy, wealthy roots vs working class roots, cautious and sane vs McAfee...)

Realistically, you need more than 51%. Andreas explains it very well, go see his videos on youtube. I can't find the link to the one I am looking for now unfortunately

If you have 51% then you only mine 1% faster than the rest of the network. This 1% can be offset by luck, and remember the main network is still mining. So realistically you won't really outpace them. Now the game theory of this is what makes bitcoin even more secure. Off a quick calculation with the current hashrate bitcoin currently has around 1.7million antminers supporting it. Buying these at $2000 per unit will cost 3.5 Billion Dollars. Then comes the facility and staff costs, electricity and all to sustain it. Once you succeed you lost all that money.

It really just isn't viable to do it, and the higher the hashrate goes the more of a waste it is.

Realistically, you need more than 51%. Andreas explains it very well, go see his videos on youtube. I can't find the link to the one I am looking for now unfortunately

If you have 51% then you only mine 1% faster than the rest of the network. This 1% can be offset by luck, and remember the main network is still mining. So realistically you won't really outpace them.

My idea is that there isn't really a time factor to it. If the operation is time sensitive, then sure the varience could affect the whole results quite a bit. You have to take into account that luck works both ways; the attacker could very well experience a streak of good luck as well. In the long run, the luck could very well even out.

If you have more hashrate than the network, you would outpace them in the long run.

Realistically, you need more than 51%. Andreas explains it very well, go see his videos on youtube. I can't find the link to the one I am looking for now unfortunately

Note that despite misleading title OP is not talking about a mere 51% attack. They are talking about remining the whole Bitcoin blockchain from scratch, basically an extreme variant of Selfish Mining -- although not with the goal to gain a financial advantage over other miners, but with the goal to utterly devaluate Bitcoin. Needless to say such an attack would require vastly more resources than a measly 51% of the network. And of course it would be a pretty pointless waste of both time and money.

What would Warren Buffet's economical motivation be to do this? I cannot see him wasting money on a cheap stunt like this. Mr McAfee is basically broke and would do anything for a little bit of attention, so if Warren Buffet really wanted to see this, he would just make Mr McAfee a redicilous offer to pay the amount he was willing to spend on the mining, towards McAfee and I bet you he would do it.

McAfee can then use that money to pay plastic surgeons to recreate a massive dick and he will once again go back to those islands paradise and have a orgy with all the young girls. <like he did, when he still had the money>

Realistically, you need more than 51%. Andreas explains it very well, go see his videos on youtube. I can't find the link to the one I am looking for now unfortunately

If you have 51% then you only mine 1% faster than the rest of the network. This 1% can be offset by luck, and remember the main network is still mining. So realistically you won't really outpace them.

My idea is that there isn't really a time factor to it. If the operation is time sensitive, then sure the varience could affect the whole results quite a bit. You have to take into account that luck works both ways; the attacker could very well experience a streak of good luck as well. In the long run, the luck could very well even out.

If you have more hashrate than the network, you would outpace them in the long run.

Yea, but the setup of doing such an attack is insane. The amount of money and resources you have to dedicate to do 1 double spend is why it will never happen. And the best thing is, the second you succeed bitcoin is worthless.

I don't think we will ever see it happen to bitcoin, plus where do you get THAT many antminers ? And have that much electricity at your disposal. If you are one player wanting to plug in that many miners, I am sure your government will stop you since you will definitely be putting a national power grid at risk.